The trigger is a "bolt on" as far as the screws holes in the tube are concerned.... You will need to widen the inletting in the stock a bit.... You should also use a hammer and striker from the Challenger or PRod as they don't have a "waist" which can impact the sear and shatter it, although some haven't changed the hammer and report no problem.... Filling the groove in the Disco hammer with JB Weld is an alternative.... If you use the cylindrical hammer from the Challenger or PRod you will have you modify the top front to clear the front breech screw in the Disco.... AFAIK, that's it.... The trigger is a far better quality than that in the Disco....

bob is correct, its a simple bolt on swap, the prod/challenger hammer is easy to mod if you have a dremel or you could contact junkyspace and see if he could do the modding to one for you ? he did a superb job on his and you can find it in the machine shop gate under the simple home mods or whatever. its the first sub gate in the machine shop gate..

That is correct, the challenger and the prod both share the same hammer. But don't forget to order the hammer assembly so you get the striker as well. The striker is adjustable for hammer throw so it gives you an added form of adjustment.

But you will still need to cut the dip in the front top of it to clear the breech screw

The PRod trigger is not a drop in fit! There was a topic about the PRod trigger fitting a Disco that did get a little nasty! It was about the sear did not reach high enough to safely engage the hammer.It did get into how to fix it but I do not remember all the details.

Actually, it was putting a PRod trigger on an MRod that was the problem.... The MRod tube is a larger radius and a thicker wall, and it was the combination of those that caused the PRod trigger to be a questionable fit and raised a safety concern.... The Disco, PRod, and 22XX tubes are all the same diameter and wall thickness, so the PRod trigger fits all of them perfectly, and functions safely.... There is also an issue putting a PRod trigger on a pumper (13XX) tube, involving the sear hitting the outside of the tube and not being able to move up far enough to cock.... This is because of the smaller diameter of the 13XX tube.... It can be easily solved by filing a bit of a flat to miss the top of the sear, or lengthening the sear slot in the tube on the front end....

Yes Bob now I remember! Seems like I had a moment of sometimers, sometimes I remember sometime I don't! LOL I new it effected me in some way as I had the PRod trigger on my MRod AR Carbine and it had been modified to work.